Interesterified blend-based and physical blend-based special fats: storage stability under fluctuating temperatures

BACKGROUND: Temperatures that special fat faces in a real environment fluctuate, thus, understanding the property changes of special fats under fluctuating temperatures will be helpful in guiding how to keep its high quality in the production and application process. Therefore, a comparative study was carried out on the storage stability of physical blend-based and interesterified blend-based special fats (PBSFs and IBSFs) and their oxidative stability, crystallization and physical properties were studied under fluctuating temperatures. RESULTS: The peroxide values of IBSFs and PBSFs were less than 10.0 mmol kg⁻¹ after 4 weeks of storage, and IBSFs had better oxidative stability. There was little change in the solid fat content, and the hardness decreased when IBSFs and PBSFs were stored for 4 weeks. X-ray diffraction results indicated that PBSFs had only β-crystal, but IBSFs had β- and β′-crystal after storage. Moreover, in IBSFs, the transformation from β′- to β-form in PS:RO-IBSF was more obvious than that in PS:SO-IBSF (PS, palm stearin; SO, soybean oil; RO, rapeseed oil) after 4 weeks of storage, and the good integrity of crystalline network in fast-frozen special fats during fluctuating temperature storage followed the order: IBSF > PBSF, PS:RO-PBSF > PS:SO-PBSF. CONCLUSION: The results suggest IBSF can better maintain its quality during fluctuating temperature storage than PBSF.